Dynamical Outcome Modeling of Fragmented Intensive Longitudinal Data

The advent of new sensing technologies has enabled the collection of high frequency individual data. Not only can this allow for the identification of personalized behavior models, it also opens up the possibility of developing just-in-time interventions that leverage the information collected to determine when and which micro intervention should be provided. However, there are significant challenges in the analysis of this type of data. First, due to the high rate of data collection, one can no longer assume that the stimulus (independent excitation or micro intervention) only has an instantaneous effect on the outcome, one has to also allow for delayed effects. Moreover, one is also frequently faced with fragmented data; i.e., poor placement of sensors, non-wear of the data collecting device and/or external disturbances can lead to intervals of time where the data collected is not reliable; i.e., missing or corrupted. To deal with these challenges, we leverage concepts from the areas of dynamical systems and signal processing to develop tools that i) can identify models that take into account the delayed stimuli effects and ii) are able to handle fragmented data. In this paper, we provide both the mathematical foundation of the tools proposed and the description of a package that implements them. We also discuss ways to interpret the results obtained.

The Effects of Fireworks Discharge on Atmospheric PM2.5 Concentration in the Chinese Lunar New Year

Discharging fireworks during the Chinese Lunar New Year celebrations is a deep-rooted custom in China. In this paper, we analyze the effect of this cultural activity on PM2.5 concentration using both ground observations and satellite data. By combining remote sensing data, the problem of uneven spatial distribution of ground monitoring has been compensated, and the research time span has been expanded. The results show that the extensive firework displays on New Year’s Eve lead to a remarkable increase in nationwide PM2.5 concentration, which were 159~223% of the average level, indicating the instantaneous effect far exceeds that of any other factor over the whole year. However, the averaged PM2.5 concentrations of the celebration period were 0.99~16.32 μg/m3 lower compared to the average values of the corresponding pre-celebration period and post-celebration period, indicating the sustained effect is not very significant. The implementation of firework prohibition policies can greatly reduce the instantaneous PM2.5 increase, but no obvious air quality improvement is observed over the entire celebration period. Combining these findings and the cultural significance of this activity, we recommend that this custom is actively maintained, using new technologies and scientific governance programs to minimize the negative effects.

Acute consequences of a unilateral VIIIth nerve transection on vestibulo-ocular and optokinetic reflexes in Xenopus laevis tadpoles

Loss of peripheral vestibular function provokes severe impairments of gaze and posture stabilization in humans and animals. However, relatively little is known about the extent of the instantaneous deficits. This is mostly due to the fact that in humans a spontaneous loss often goes unnoticed initially and targeted lesions in animals are performed under deep anesthesia, which prevents immediate evaluation of behavioral deficits. Here, we use isolated preparations of Xenopus laevis tadpoles with functionally intact vestibulo-ocular (VOR) and optokinetic reflexes (OKR) to evaluate the acute consequences of unilateral VIIIth nerve sections. Such in vitro preparations allow lesions to be performed in the absence of anesthetics with the advantage to instantly evaluate behavioral deficits. Eye movements, evoked by horizontal sinusoidal head/table rotation in darkness and in light, became reduced by 30% immediately after the lesion and were diminished by 50% at 1.5 h postlesion. In contrast, the sinusoidal horizontal OKR, evoked by large-field visual scene motion, remained unaltered instantaneously but was reduced by more than 50% from 1.5 h postlesion onwards. The further impairment of the VOR beyond the instantaneous effect, along with the delayed decrease of OKR performance, suggests that the immediate impact of the sensory loss is superseded by secondary consequences. These potentially involve homeostatic neuronal plasticity among shared VOR-OKR neuronal elements that are triggered by the ongoing asymmetric activity. Provided that this assumption is correct, a rehabilitative reduction of the vestibular asymmetry might restrict the extent of the secondary detrimental effect evoked by the principal peripheral impairment.

Instantaneous Effect of Insole on the Balance of Adolescents With Flat Foot and Pes Cavus

Objective: The purpose of this study was to examine the instantaneous effect of insole on the balance of adolescents with flat foot and Pes Cavus. Methods: In this quasi-experimental study, 34 adolescents with flat foot and Pes Cavus (17 girls and 17 boys) in the age range of 11 to 14 years in Tehran were randomly selected and their balance performance in static and dynamic positions was examined before and after instantaneous using of insole. Data were analyzed using paired t-test and independent t-test. Results: Paired t-test results showed that the instantaneous effect of insole on dynamic balance is significant (P=0.00), but it had no significant effect on static balance (P=0.07). The results of independent t-test showed no significant difference between the two groups in terms of dynamic balance (P=0.99) and static balance (P=0.52) in Pre-test phase. There was no significant difference between the two groups in dynamic balance (P=0.25) and static balance (P=0.72) in Post-test phase, either. Conclusion: Using medical insole can improve the dynamic balance in adolescents with Pes Cavus and flat foot, but has no effect on their static balance.

Nonlinear impact of World Heritage Sites on China’s tourism expansion

Using domestic tourism data (1999–2014) and inbound tourism data (1999–2016), this research applies linear and nonlinear models to investigate the impact of World Heritage Sites (WHS) on inbound and domestic tourism expansion (TE) in terms of tourist arrivals and tourism receipts and then tests whether or not the impact of WHS on TE is instant. The results show a notable influence of WHS on tourist arrivals and tourism receipts and identify several differences between the impacts of WHS on inbound and on domestic TE. Moreover, the relationship between WHS and TE exhibits an inverted U-shaped curve. The optimal number of WHS for TE is four, and there is a significant instantaneous effect of WHS on domestic TE. Differently, the impact of WHS on inbound tourism shows a 1-year lag. Lastly, we perform dynamic regressions as a robustness check and discussion and implications are provided.